# from math import *
# a = log(112,4)
# b = int(a)
# print(a)
# print(b)

# n = 123
# a = list(int(str(n)))
# print(len(str(n)))
# print(a)

# a = [[0,1,0,0],
#  [1,1,1,0],
#  [0,1,0,0],
#  [1,1,0,0]]
# print(a[1])
# candies = [1,1,2,2,3,3]
# c = []
# a = set(candies)
# for i in a:
#     c.append(i)
# print(candies)
# print(a)
# print(c)

# candies = [1,1,2,3]
# length = len(candies)
# each = length // 2
# type_dict = dict()
# type_cnt = 0
#
# for c in candies:
#     if type_dict.get(c, 0) == 0:
#         type_dict[c] = 1
#         type_cnt += 1
#
# if type_cnt >= each:
#     print(each)
# else:
#     print(type_cnt)

# import os
# cmd = "test.cmd"
# os.popen(cmd)

# words = ["Hello", "Alaska", "Dad", "Peace"]
# set1 = set('qwertyuiop')
# set2 = set('asdfghjkl')
# set3 = set('zxcvbnm')
# res = []
# for i in words:
#     x = i.lower()
#     setx = set(x)
#     if setx<=set1 or setx<=set2 or setx<=set3:
#         res.append(i)
# print(res)

# a = "a"
# b = "d"
# if a<= b:
#     print(True)
# else:
#     print(False)

# a = ["rrjk","furt","guzm"]
# b = []
# c = []
# n = 0
# count = 0
# l = len(a[0])
# for i in range(l):
#     for j in range(1,len(a)):
#         if a[j][i]<a[j-1][i]:
#             c.append(i)
# print(c)
# a = ["rrjk","furt","guzm"]
# # b =zip(*a)
# # print(list(b))

# a = [1,2,3,3,4,3]
# b = sum(a)
# c = sum(set(a))
# print(b)
# print(b-c)
#
# a = [0] * 10
# a[1] = 1
# print(a)

# A = [4,2,5,7]
# ia = [i for i in A if not (i % 2)]
# ja = [i for i in A if i % 2]
# for n in zip(ia,ja):
#     for i in n:
#         print(i)
#         print(i)
#
# A = "AB"
# b = 0
# n = len(A) -1
# for i in A:
#     a = ord(i)
#     b = (a - 64)*26**n + b
#     n = n-1
# print(b)
# print(len(A))
from pylint.checkers import similar

# S = "loveleetcode"
# C = 'e'
# s = S.split(C)
# print(s)
# b = []
# for i in range(len(s)-1):
#     if len(s[i]) >= len(s[i+1]):
#         n = len(s[i])
#         while (n!=-1):
#             b.append(n)
#             n = n - 1
#     else:
#         a = len(s[i])+len(s[i+1])
#         n = 0
#         while(n == a//2):
#             b.append(n)
#             n = n + 1
#
# print(b)

# n = len(S) - 1
# res = []
# for i in range(n + 1):  # 遍历字符串
#     x = 0
#     while True:
#         if 0 <= (i - x) <= n:  # 判断左查找索引是否存在
#             if S[i - x] == C:
#                 res.append(x)
#                 break
#         if 0 <= (i + x) <= n:  # 判断右查找索引是否存在
#             if S[i + x] == C:
#                 res.append(x)
#                 break
#         x += 1
# print(res)

# A = ["bbddabab","cbcddbdd","bbcadcab","dabcacad","cddcacbc","ccbdbcba","cbddaccc","accdcdbb"]
# a = []
# for i in A[0]:
#     count = 0
#     for j in range(1, len(A)):
#         if i in A[j]:
#             count += 1
#             A[j] = A[j].replace(i," ",1)
#     if count == len(A)-1:
#         a.append(i)
# print(a)


# board = [[".",".",".",".",".",".",".","."],[".",".",".","p",".",".",".","."],[".",".",".","p",".",".",".","."],["p","p",".","R",".","p","B","."],[".",".",".",".",".",".",".","."],[".",".",".","B",".",".",".","."],[".",".",".","p",".",".",".","."],[".",".",".",".",".",".",".","."]]
# count = 0
# for i in range(8):
#     if "R" in board[i]:
#         c = board[i].index("R")
#         for j in range(c, -1, -1):
#             if board[i][j] == "B":
#                 break
#             elif board[i][j] == "p":
#                 count += 1
#                 break
#         for m in range(c + 1, 8):
#             if board[i][m] == "B":
#                 break
#             elif board[i][m] == "p":
#                 count += 1
#                 break
#         for jj in range(i, -1, -1):
#             if board[jj][c] == "B":
#                 break
#             elif board[jj][c] == "p":
#                 count += 1
#                 break
#         for mm in range(i + 1, 8):
#             if board[mm][c] == "B":
#                 break
#             elif board[mm][c] == "p":
#                 count += 1
#                 break
#         print(count)
#
# a = similar

# a = 6
# b = bin(a)
# n = b.count("1")
# print(b)
# print(n)
#
# L = 842
# R = 888
# count = 0
# m = True
# for i in range(L, R + 1):
#     a = bin(i)
#     n = a.count("1")
#     if n >= 2:
#         for j in range(2, int(n ** 0.5) + 1):
#             if n % j == 0:
#                 m = False
#                 break
#         if m:
#             count += 1
#             m = True
# print(count)

# a = 123
# b = str(a)[::-1]
# print(b)
#
# c = str(100)
# b = c.rstrip("0")
# print(b)
# print(c[::-1])

# ops =["5","2","C","D","+"]
# sums = 0
# temp = 0
# a = []
# for i in ops:
#     if i == "C":
#         sums = sums - a[-1]
#         a.pop()
#     elif i == "D":
#         temp = a[-1] * 2
#         a.append(temp)
#         sums = sums + temp
#     elif i == "+":
#         temp = a[-1] + a[- 2]
#         a.append(temp)
#         sums = sums + temp
#     else:
#         temp = int(i)
#         sums += temp
#         a.append(temp)
# print(sums)

# nums = [1,3,5,6]
# # target = 2
# # n = len(nums)
# # l = 0
# # r = n - 1
# # res = -1
# # while (l <= r):
# #     mid = (l + r) // 2
# #     if (nums[mid] == target):
# #         print(mid)
# #     elif (nums[mid] > target):
# #         r = mid - 1
# #     else:
# #         l = mid + 1
# # res = l
# # print(res)

# nums = [-2,1,-3,4,-1,2,1,-5,4]
# for i in range(1, len(nums)):
#     # nums[i-1]代表dp[i - 1]
#     nums[i] = max(nums[i], nums[i] + nums[i - 1])
#
# print(max(nums))
# s = "hello boboy"
# print(len(s))
# s = s.split(" ")
# print(len(s[-1]))

# a = 1
# for i in range(1,a):
#     print(i)
n = 801
numA=ord("A")
res = ''
while n // 26 > 0:
    res = chr((n-1)%26 + numA) + res
    n = (n-1) // 26
if n != 0:
    res = chr(n-1+numA) + res
print(res)